Repeated Covid-19 boosters not a viable strategy: WHO experts

World Health Organisation (WHO) experts warned on Tuesday that repeating booster doses of the original Covid-19 vaccines is not a viable strategy against emerging variants and called for new jabs that better protect against transmission.

An expert group created by the WHO to assess the performance of Covid-19 vaccines said simply providing fresh jabs of existing vaccines as new strains of the virus emerge was not the best way to fight the pandemic.

“A vaccination strategy based on repeated booster doses of the original vaccine composition is unlikely to be appropriate or sustainable,” the WHO Technical Advisory Group on Covid-19 Vaccine Composition (TAG-Co-VAC) said in a statement.

The group said there could be a need to update the existing vaccines to better target emerging variants, like Omicron which has spread rapidly and has been detected in 149 countries so far.

Prevent infection

“Covid-19 vaccines that have high impact on prevention of infection and transmission, in addition to the prevention of severe disease and death, are needed and should be developed,” TAG-Co-VAC said.

This, it said, would help lower “community transmission and the need for stringent and broad-reaching public health and social measures.”

It also suggested that vaccine developers should strive to create jabs that “elicit immune responses that are broad, strong, and long-lasting in order to reduce the need for successive booster doses”.

According to the WHO, 331 candidate vaccines are currently being worked on around the world.

Until new vaccines have been developed, the group said, “the composition of current Covid-19 vaccines may need to be updated”.